I learned the hard way that my 2006 F150 with the 3 Valve 5.4 engine uses a variable timing system that reads off the oil pressure. The engine had 150000 miles on it, but always runs great. I changed the oil before a trip with my small 5th wheel and got into traffic and the truck began stumbling and died. Fired right back up and ran fine about 1000rpm, just would not idle. I found solution in posts that it was the oil pressure dropping too low (below 25 lbs) which caused the timing to change, so posting advice was to put in a slightly heavier weight oil, which solved everything immediately. As I am looking to buy a 2009 or later F350 Super Duty 2WD Dually with a V-10 and want to know, does this engine have the two piece spark plug problem or the variable timing/oil pressure issue like the 5.4?

 

I don't think anything after mid 07 had the plug issues. Not sure on any oil pressure issues though

 

Spark plug issue was fixed in 2008. V10 never got the VVT. 2008-2010 V10 is your truck to buy!

 

its too bad the v10 never got vvt, imagine the low end TQ it could have gained, hey Ford where is our 7.8 liter coyote boss 520 hp 550 ft lb v-10?

 

Uwh! Yeah Ford, I want a 6.2 with 2 more cylinders glued on!!!

 

And I am just as glad Ford left the VVT off my V10! I see to many ticking 5.4's, including the one I still own!

 

Oil pressure activated VVT should never have been added to any engine. Electric activation maybe ok, I don't know.

The lackadaisical who miss an oil change by a large margin can ruin a new engine by causing sludge in the small ports that cannot be cleaned.

 

Oil activated VVT does work, just look at 2000+ Corolla, and many others. Ford just dropped the ball adding it to their great modular motors. Again, so glad they left the V10 out! I Wonder why they omited it anyway?

 

Probably because it didn't need any more low end torque and no one buying them cared about gas mileage like the majority of 5.4 sold in the 150.